The present invention relates to a double layer sock. More particularly, the present invention relates to a sock having two layers of the same or different material connected together at spaced locations with tuck stitches and to a method for making the sock.
Double layer socks provide additional cushioning of the foot when the wearer is engaged in activities such as running, hiking and the like. Such socks also may be made to be particularly effective at absorbing perspiration. Double layer socks provide for movement between the layers thereby reducing the movement between the inner layer and the wearer""s foot, resulting in a more comfortable fit. Single, as well as double layer socks are generally knit as a sock blank with a cuff or welt surrounding an opening at the leg portion and an opening at the toe portion. The toe opening of a machine knit sock is then closed.
One means of cushioning socks is to produce a pair of socks with a terry layer such as that disclosed in U.S. Pat. No. 3,796,0675 to East in which the sock has a smooth knit outer layer and an inner layer having terry loops on both inner and outer surfaces. East teaches forming the sock by knitting a single elongated tube on one-half of which is of smooth knit fabric and one-half is a terry knit fabric. Then the terry knit portion is everted within the other half to achieve two layers, and closing the toe. Thus, the double layers of the sock of East are connected only at the leg opening and at the toe closure.
A double layer sock is also disclosed in U.S. Pat. No. 4,571,690 to Hursh et al. which describes an athletic sock having a double-ply foot portion including an inner ply with an inner surface comprising a plurality of substantially untwisted fibers around which a yarn is spirally wound and an outer surface comprising yarns having relatively low friction characteristics. The outer ply, within which the first ply is disposed, has an inner surface comprising yarns having relatively low friction characteristics and an outer surface comprising a plurality of substantially untwisted fibers around which a yarn is spirally wound to provide low-friction interface surfaces. Similar to the East sock, the Hursh sock is knit from a single tube and everted so that the inner ply fits within the outer ply, with the plies connected only at the top and at the toe.
Another form of a double layer sock is disclosed in U.S. Pat. No. 4,958,507 to Allaire et al. The method of making the sock begins with knitting a first course that is transferred to a transfer plate (also known as a dial plate) to remain in standby while the balance of the double layer sock body is knitted. The retained first course is then transferred from the dial plate at the end of the knitting process to form a connection between the inner layer and the outer layer at the toe. When the inner and outer layers are connected at the toe, additional courses are knit to form a single tubular terminal layer that extends beyond the two sock layers that is used to close the toe on a seaming machine. Thus, there is no seam at the opening of the leg, but only the fold.
Another double layer sock construction is disclosed in U.S. Pat. No. 6,158,254 to Richard. The inner layer is knit in a first tubular segment of normal stitch density and a second tubular segment of low knit density and then the balance of the sock body is knit with normal stitch density to complete the inner layer of the sock. The knitting continues with an outer layer of the sock joined to the inner layer along a fold line and having normal stitch density. The inner and outer layers are maintained with their wales aligned. The sock is discharged from the knitting machine and transferred to a toe-closing machine.
Despite the advantages of the above described socks, it has been found desirable to provide a double layer sock having layers of different material and to provide a method for connecting the layers together at spaced locations during the knitting operation.
The present invention is directed to a sock with a knit liner or to phrase it differently, a layered sock. The sock is knit of double layer construction formed on a circular knitting machine. The sock has a foot portion extending from the toe to the heel pocket and a leg portion extending from the heel pocket to an upper cuff portion. The sock includes a tubular inner layer having a foot portion and a leg portion merging substantially at the ankle of a wearer and a tubular outer layer surrounding the inner layer. The outer layer has a foot portion and a leg portion merging substantially at the ankle of the wearer and aligning with said foot portion and leg portion, respectively, of the inner layer. The inner layer and the outer layer have a cuff portion at the top of the leg portion. The inner and outer layers are connected at spaced locations by tuck stitches during the knitting operation. The sock is then discharged from the knitting machine and transferred to a toe closing machine. In a preferred embodiment of the invention the inner layer and the outer layer may be knit using different yarns.
The present invention also provides a method of making such a double layer sock of unitary tubular construction. Knitting of the outer layer and the inner layer occurs simultaneously.
It is a general object of the present invention to provide a double layer sock, especially one that can be knit from different materials.
Another object of the present invention is to provide a method for knitting a double layer sock.